Seniors: Cannabinoids In Parkinson’s Disease

Recently there has been a lot of interest in medical Cannabinoids as medications for a variety of aging-related diseases, Parkinson’s disease being one of them. I have also received letters from a few readers living with Parkinson’s disease, wanting to know whether medical Cannabinoids would work for them.

Are medical Cannabinoids beneficial for individuals living with Parkinson’s disease? What does the research evidence show?

But before we explore those questions, it is essential to understand what we mean by medical Cannabinoids. Medical cannabinoids include medical marijuana (dried marijuana and marijuana oils) and synthetic cannabinoids.

A recent case study involving a 70-year-old woman with Parkinson’s disease, who developed psychosis following a couple of doses of a synthetic Cannabinoid, is very relevant here. She was diagnosed with Parkinson’s disease 12 years ago and was taking the standard treatment of Levodopa/Carbidopa, which improved her symptoms initially.

When the medications started wearing off, she developed chronic and painful involuntary movements, and cramping and painful contractions of the legs and feet. A friend with Parkinson’ disease advised her to try medical marijuana, and she discussed the idea with her physician.

Her physician prescribed a synthetic Cannabinoid Nabilone. Just after taking 2 doses she developed visual hallucinations (seeing things that do not exist), panic and paranoia (suspicion and mistrust of people and their actions) within hours. These symptoms of psychosis became worse over the next three weeks, despite discontinuing Nabilone. She also had delusions (very firm, but false belief) that her neighbours were engaged in dangerous and illegal activities.

Before taking Nabilone, she had occasional visual hallucinations for many years, but her insight into these hallucinations was intact, and she was able to live independently, despite mild cognitive concerns. She had no other active concurrent problems, and her medications were same as before.

However, just 3 weeks after the couple of doses of Nabilone, she scored poorly in the assessment of her attention, orientation, abstraction and delayed recall. Her delusions and hallucinations persisted and worsened.

This case illustrates the potential of synthetic cannabinoid Nabilone to trigger psychosis in a susceptible person. Moreover, patients with Parkinson’s disease may develop psychosis as part of natural history of the disease, or due to external triggers such as infections and dopaminergic drugs.

Synthetic Cannabinoids are licensed in Canada for selected conditions, such as management of chemotherapy induced nausea, chronic pain, and spasticity associated with Multiple Sclerosis. Though there are some anecdotal claims of improvement in shaking/tremors, and involuntary movements in Parkinsonism, there is very little scientific evidence to support these claims.

In fact the current evidence for the use of Cannabinoids to manage motor symptoms in Parkinson’s disease is sparse, observational, and of low quality.

Many symptoms of Parkinson’s disease being incompletely or poorly responsive to medical and surgical treatments, people turn to medical marijuana and Cannabinoids, thinking they are natural and safe. They might also be encouraged by their peers or by videos on the internet to try it. They are likely to be unaware of the potential harmful effects of marijuana and cannabinoids.

Some of the common harmful effects of marijuana and Cannabinoids include decreased blood pressure, fainting, stroke, heart attack, bronchitis, asthma, suppression of immunity leading to infections, nausea, and excessive vomiting. They can also affect short term memory, attention, executive functioning, and visual perception, and cause anxiety, panic attacks, depression, hallucinations, and even permanent psychosis.

Persons with Parkinson’s disease have an inherent risk of psychosis and cognitive impairment. They are more susceptible to the cognitive and psychosis-inducing effects of cannabinoids. Therefore, we can safely conclude that the potential risks of the use of cannabinoids outweigh the benefits in persons with Parkinson’s disease.

Padmaja Genesh, who holds a bachelor degree in medicine and surgery as well as a bachelor degree in Gerontology, has spent several years teaching and working with health care agencies. A past resident of Red Deer, and a past board member of Red Deer Golden Circle, she is now a Learning Specialist at the Alzheimer Society of Calgary. Please send your comments to padmajaganeshy@yahoo.ca